1. Technical Field of the Invention
The invention is related to undersea vehicle motor cooling mechanisms and more particularly to self-powered cooling systems.
2. Description of the Prior Art
There are numerous devices for cooling systems for undersea vehicle motors in the prior art. An undersea vehicle can be any type of small autonomous undersea craft such as a torpedo. Typically, these devices have provided liquid cooling, sometimes with phase change, to housing or motor assemblies. Representative patents include U.S. Pat. No. 3,964,416 to Kiraly et al. and U.S. Pat. No. 4,680,934 to Short. Technical difficulties involved in undersea vehicle cooling systems include the necessity to produce a wake having low observables thereby avoiding easy detection. To reduce observables, the cooling system should avoid discharges having high temperature gradients, having high gas or steam concentrations, and having high turbulence levels. Additionally, the cooling system itself should not produce additional noise caused by pumps or other mechanisms. Finally, a cooling system for a torpedo must operate over a range of depths and pressures. In current designs, some torpedoes depend on limited heat transfer to the ocean water along with short mission duration to permit short-term operation without a sufficient amount of cooling to allow extended steady state operation. This lack of sufficient cooling prevents the use of torpedo components for new and emerging technologies, such as remotely operated or autonomous underwater vehicles. Also, the limited heat transfer presents a cooling problem during out-of-water testing or even during extended in-water testing.